This invention relates generally to automatic car wash systems and more particularly to improved vehicle dry wiper arrangements of the endless conveyor curtain drier type for use in such systems.
Mechanical wiping arrangements have been proposed to substantially dispose with conventional air drying and hand wiping operations. Typically of these are the rotary dry wiping systems of U.S. Pat. No. 3,914,818 which comprise one or a pair of multi-arm rotor assemblies suspending wiping strips which, as the rotor turns about a vertical axis, pass over the vehicle surface. Such operations are large and cumbersome, are generally confined to use of narrow outboard strips limiting drying effectiveness and requiring substantial power for operation. Another system is that shown in U.S. Pat. No. 3,504,394 utilizing a combination of wiping and air drying and wherein an endless chain conveyor of two parallel chains is employed, the lower chain carrying suspended towels over the vehicle to effect drying and then upwardly where the towels are dried and then by the upper chain back to the starting point. When carried by the upper chain the adjacent towels because of their suspended length and spacing overlap and adhere to each other with substantial cohesiveness to produce a laminate effect. As a result the towels are still lying on the upper chain area when their top or supported portions reach the lower chain. Hence the towels do not hang free or become effective drying instruments until a substantial distance from the head end of the system. Valuable working space available for free hanging towels is thereby lost in the drying area of the system. It has also been suggested to utilize large drums as in U.S. Pat. Nos. 3,940,821 and 4,087,877 the latter equipped with pivoted plate assists to aid in unlaminating the towels. In both there is a reduction in the number of effective towels brought to the drying area by these massive and power consuming structures. Moreover in the latter patent the towel movement engendered by the pivotal plates is minimal and there results an uneven spacing of the towels encountering the wet vehicle surface.